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            <div id="ConfluenceContent"><p>Velocity is a templating language for Java.</p>

<p>For more information on Velocity itself, please visit the <a shape="rect" class="external-link" href="http://velocity.apache.org/">Velocity website</a>.</p>
<div class="confluence-information-macro confluence-information-macro-information"><span class="aui-icon aui-icon-small aui-iconfont-info confluence-information-macro-icon"></span><div class="confluence-information-macro-body"><p>Velocity is similar to <a shape="rect" href="freemarker.html">FreeMarker</a>, as both are template languages that can be used outside of a Servlet container. The framework uses FreeMarker internally since it has better error reporting. Developers may also like that FreeMarker supports JSP taglibs. However, both are good alternatives to JSP.</p></div></div>

<h2 id="Velocity-GettingStarted">Getting Started</h2>

<p>Getting started with Velocity is as simple as ensuring all the dependencies are included in your project's classpath. Other than that, <a shape="rect" href="struts-defaultxml.html">struts-default.xml</a> already configures the <a shape="rect" href="velocity-result.html">Velocity Result</a>.</p>
<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>struts.xml</b></div><div class="codeContent panelContent pdl">
<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;">
&lt;action name="test" class="com.acme.TestAction"&gt;
    &lt;result name="success" type="velocity"&gt;test-success.vm&lt;/result&gt;
&lt;/action&gt;
</pre>
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<div class="code panel pdl" style="border-width: 1px;"><div class="codeHeader panelHeader pdl" style="border-bottom-width: 1px;"><b>test-success.vm</b></div><div class="codeContent panelContent pdl">
<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;">
&lt;html&gt;
&lt;head&gt;
    &lt;title&gt;Hello&lt;/title&gt;
&lt;/head&gt;
&lt;body&gt;

Hello, ${name}

&lt;/body&gt;
&lt;/html&gt;
</pre>
</div></div>
<p>Where <code>name</code> is a property on the Action class. That's it!</p>

<p>There are few more details of interest, such as how templates are loaded and variables are resolved.</p>

<h2 id="Velocity-TemplateLoading">Template Loading</h2>

<p>The framework looks for Velocity templates in two locations (in this order):</p>
<ol><li>Web application</li><li>Class path</li></ol>


<p>The ordering is designed so that a default set of templates can be placed in a JAR (perhaps shared between applications). If a template needs to be overridden, a different version can be placed in the web application.</p>
<div class="confluence-information-macro confluence-information-macro-tip"><p class="title">Just the JARs, Ma'am</p><span class="aui-icon aui-icon-small aui-iconfont-approve confluence-information-macro-icon"></span><div class="confluence-information-macro-body">
<p>Unlike JSPs, templates can be loaded from a JAR. Templates are a great way to support "plugins", since the entire module can be delivered in a single JAR, and the views easily customized by the host application.</p></div></div>

<h2 id="Velocity-VariableResolution">Variable Resolution</h2>

<p>In Velocity, there are three sources for variables, searched in a specific order.</p>
<ol><li>The value stack</li><li>The action context</li><li>Built-in variables</li></ol>


<p>Since the action context is resolved after the value stack, you can reference the variable without the typical preceding marker (#) that has to be used with the JSP <code>s:property</code> tag. Omitting the marker can be convenient, but it can also trip you up, if used carelessly.</p>
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<pre class="brush: xml; gutter: false; theme: Default" style="font-size:12px;">
#surl "id=url" "value=http://www.yahoo.com"
Click &lt;a href="${url}"&gt;here&lt;/a&gt;!
</pre>
</div></div>
<p>The Stuts2-Velocity integration layer provides several implicit variables.</p>
<div class="table-wrap"><table class="confluenceTable"><tbody><tr><th colspan="1" rowspan="1" class="confluenceTh"><p> Variable </p></th><th colspan="1" rowspan="1" class="confluenceTh"><p> Description </p></th></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> stack </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> The value stack itself, useful for calls like ${stack.findString('ognl expr')} </p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> action </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> The action most recently executed </p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> response </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> The HttpServletResponse </p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> res </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> Same as response </p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> request </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> The HttpServletRequest </p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> req </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> Same as request </p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> session </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> The HttpSession </p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> application </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> The ServletContext </p></td></tr><tr><td colspan="1" rowspan="1" class="confluenceTd"><p> base </p></td><td colspan="1" rowspan="1" class="confluenceTd"><p> The request's context path </p></td></tr></tbody></table></div>


<h2 id="Velocity-ConfiguringVelocity">Configuring Velocity</h2>

<p>You can configure Velocity by placing configuration items in <a shape="rect" href="velocityproperties.html">velocity.properties</a>.</p>

<h2 id="Velocity-Next:">Next: <a shape="rect" href="velocity-tags.html">Velocity Tags</a></h2></div>
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